Improvement in variable cut-ofr for steam-engines



, or experiment.

`wheel and screw, and makes the distance between the -cams, greater or less, so that the point at which steam thecam D brought nearer to or removed from the im @uw MLcHAEL c. TAYLOR, or eRAssl VALLEY, cALrroRNLA.

Letters Patent No. 98,122, dated .December 21, 1869; antedatell December 17, 1869. g

mPRovr-.MENT IN VARIABLE CUT-orr- I'oR STEAM-ENGINES.

The Schedule referred to in these Lettera Patent and making part of the same.

To all whom it may concern Be it' known that I, MICHAEL C. TAYLOR, of Grass Valley, county of Nevada, State of California, have invented an Improved Variable Cut-Off for Steam- Engines; and I do hereby declare the following description and accompanying drawingsare suiicient to enable any person skilled in` the art or science to which it most nearly appertains to make and use my said invention, or improvement, without further invention My invention relates to that portion of the mechanism of a steam-engine, by which the admissionof steannto the cylinder is regulated, and consists in an improved device, b y which the steam is cut oil', after the piston has accomplished a portion of its stroke. rihis isdoue by two cams, which act upon the valvestem, more or less directly, one of which opens the valve, and the other, followingr it, moves it s till further, and closes the steam-port, but leaves the exhaust-port slight-ly open.

The last, or cntoii cam, isattached to a cylinder, having spiral grooves onthe inside.

A follower, or plunger, having projections which tit these grooves, is moved back or forward, by a handshall be cut off is easily changed and regnlatedf Referring to the accompanying drawings- Figure 1 is a Vlongitudinal vertical section.

'Figure 2 is an end view. t Similar letters of reference in each of the figures indicate like parts.

A is a slide, which connects with the valve, and has a space, formed by the shoulders or project-ions B B', within which the cams G and D turn, and, by striking these shoulders, lnove the valve backward and forward.

The cani C has a short, hollow shaft, E, and may be actuated by a mitre-gear, or other suitable device.

.-lhe .cam D is fastened to a hollow cylinder, F, which has the spiral grooves t on the inside. v

Afollower, G, is fitted to movel within this cylinder, and has projecting` lugs or feathers c, which fit into the grooves ll', and, as the follower is moved toward one end or the other, the cylinder will be turned, and

cam G. The follower is moved by means of a long screw, H,

which is attached to one side of the follower bya swivel, d, which allows the follower and cylinder to turn, without turning the screw.

rlhe screw passes ii'eely'throngh the end ofthe cylinder, as shown at I, and then passes through a nut, J, which is turned within'its stationary bearing K, by a hand-wheel, L, so as to move the follower from one end to the other of the cylinder: l

To prevent the friction of the follower from rotating the screw, 'a groove is cut, longitudinally, in the lower part of the screw, and the top of the pos't M projects into it, suiieiently to 'prevent the screw from turning, thus making its motior merely forward and back.

- In order to rotate the cylinder F, follower G, and

the cam D, a square shaft, N, is fastened to the fol.-

lower, on the side4 opposite .the screw, and passes through the hollow shaft E of the cam C, fitting so that it must move with it.

The* operation is as follows: l

The engine being in motion, the' cam C, striking one of the shoulders B, moves the valve so far as to open the steam-port 011 one side, and the exhaust-port at the opposite endLso that the steam follows the piston, till the cam 1) strikes the same shoulder, and moves the yalve still further along, entirely closing the imluction-port, but still leaving the exhaust-port slightly open; the`pistou then complet-es its stroke, by the expansion ofthe steam' already in the cylinder;v the cams continue their (revolution, strike the other shoulder B', with a similar result, at the other end of the cogne-cylinder. By turning the hand-wheel L, as previously described, the cams are brought nearer together, or are moved further apart, this being done y without stopping the engineand the point at which steam is cnt otf is regulated.

Having thus Adescribed my invention,

lhe arrangement, with reference to the projections B andB, and the cam C, of the cylinder F, provided with the cam D, and spiral grooves a, and the arrangement, within said cylinder, of the follower G, screw H,

and sliding stem N, whereby the position of the cam D, relatively to C, may be readily adjusted, substan tia-lly as described.`

' In witness whereof', I have hereunto set my hand and seal. i

Witnesses: MICHAEL (ITAYLOR. [L s] WILLIAM STAINFOMH, J. L. BOONE. 

